/**************************************************************************\
 * Copyright (c) Kongsberg Oil & Gas Technologies AS
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of the copyright holder nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
\**************************************************************************/

/*!
  \class SoCounter SoCounter.h Inventor/engines/SoCounter.h
  \brief The SoCounter class is an integer counter engine.

  \ingroup engines

  The engine counts from its \a min value to its \a max value, adding
  the value of \a step each time \a trigger is touched.

  SoCounter provides a convenient way of keeping track of the number
  of times some event in your application is triggered.
*/

/*!
  \var SoSFShort SoCounter::min
  Minimum value for counter.
*/

/*!
  \var SoSFShort SoCounter::max
  Maximum value for counter.
*/

/*!
  \var SoSFShort SoCounter::step
  Counter step value.
*/

/*!
  \var SoSFTrigger SoCounter::trigger
  Increment counter (using step).
*/

/*!
  \var SoSFShort SoCounter::reset
  Reset counter to this value. The value will be clamped between min
  and max, and step will be accounted for.
*/

/*!
  \var SoEngineOutput SoCounter::output
  (SoSFShort) Output which contains the current counter value.
*/


/*!
  \var SoEngineOutput SoCounter::syncOut
  (SoSFTrigger) Triggers every time counter restarts at SoCounter::min.
*/

#include <Inventor/engines/SoCounter.h>
#include <Inventor/lists/SoEngineOutputList.h>

#include "engines/SoSubEngineP.h"

SO_ENGINE_SOURCE(SoCounter);

/*!
  Default constructor.
*/
SoCounter::SoCounter(void)
{
  SO_ENGINE_INTERNAL_CONSTRUCTOR(SoCounter);

  SO_ENGINE_ADD_INPUT(min, (0));
  SO_ENGINE_ADD_INPUT(max, (1));
  SO_ENGINE_ADD_INPUT(step, (1));
  SO_ENGINE_ADD_INPUT(trigger, ());
  SO_ENGINE_ADD_INPUT(reset, (0));

  SO_ENGINE_ADD_OUTPUT(output, SoSFShort);
  SO_ENGINE_ADD_OUTPUT(syncOut, SoSFTrigger);

  this->syncOut.enable(FALSE);  // Disable notification

  this->value = 0;
  this->numsteps = 0;
}

/*!
  Destructor.

  Protected, as engines are not supposed to be explicitly deleted, but
  rather take care of their own destiny by monitoring their reference
  count.
*/
SoCounter::~SoCounter()
{
}

/*!
  \copybrief SoBase::initClass(void)
*/
void
SoCounter::initClass()
{
  SO_ENGINE_INTERNAL_INIT_CLASS(SoCounter);
}

// doc in parent
void
SoCounter::evaluate()
{
  SO_ENGINE_OUTPUT(output,SoSFShort,setValue(this->value));
}

// doc in parent
void
SoCounter::inputChanged(SoField *which)
{
  // Default to not notifying fields connected to the syncOut output.
  this->syncOut.enable(FALSE);

  if (which == &this->trigger) {
    this->numsteps += 1;
    this->value += this->step.getValue();
    if (this->value > this->max.getValue()) {
      this->value = this->min.getValue();
      this->numsteps = 0;
      this->syncOut.enable(TRUE);
    }
    else if (this->value < this->min.getValue()) {
      this->value = this->max.getValue();
      this->numsteps = 0;
      this->syncOut.enable(TRUE);
    }
  }
  else if (which == &this->reset) {
    short minval = this->min.getValue();
    short maxval = this->max.getValue();
    short resetval = this->reset.getValue();
    if (resetval < minval) {
      this->numsteps = 0;
      this->value = minval;
    }
    else {
      if (resetval > maxval) resetval = maxval;
      short stepval = this->step.getValue();
      this->numsteps = (resetval - minval) / stepval;
      this->value = minval + this->numsteps * stepval;
    }
  }
  else if (which == &this->max) {
    if (this->max.getValue() < this->min.getValue()) {
      this->min.setValue(this->max.getValue());
      this->value = this->max.getValue();
      this->numsteps = 0;
    }
    if (this->max.getValue() < this->value) {
      this->value = this->min.getValue();
      this->numsteps = 0;
    }
  }
  else if (which == &this->min) {
    if (this->max.getValue() < this->min.getValue()) {
      this->max.setValue(this->min.getValue());
      this->numsteps = 0;
    }
    this->value = this->min.getValue() + this->step.getValue() * this->numsteps;
    if (this->value > this->max.getValue()) {
      this->numsteps = 0;
      this->value = this->min.getValue();
    }
  }
  else if (which == &this->step) {
    this->value = this->min.getValue() + this->step.getValue() * this->numsteps;
    if (this->value > this->max.getValue()) {
      this->numsteps = 0;
      this->value = this->min.getValue();
    }
  }
}
